That leaves 27 Oireachtas members from whom Norris can seek support, but at this stage he seems assured of the backing of just 11, eight TDs and three Senators.

The eight TDs who are committed to support Norris’s nomination are four members of the United Left Alliance – Joe Higgins, Clare Daly, Richard Boyd Barrett and Joan Collins – along with Catherine Murphy, Stephen Donnelly, Mick Wallace and Maureen O’Sullivan.

From the Seanad, as well as his own vote he can rely on NUI Senator John Crown and Seán Barrett from Trinity College.

Norris will struggle to get nine more supporters from the remaining 16 available Oireachtas members.

Some of them have ruled out supporting him, some of them will not back any candidate and a number are refusing to say what they will do.

Michael Lowry, Mattie McGrath, Noel Grealish and Shane Ross have declined to support Norris while two more, Thomas Pringle and John Halligan, who initially backed him, withdrew their support in July and have given no indication of reversing their stance.

Séamus Healy is the only member of the United Left Alliance who has not declared what he will do but he has given no indication to date that he will support Norris.

When the seven TDs are taken out of the equation, there are nine Senators left and Norris would need to get the support of all of them to get a nomination.

That appears highly unlikely.

NUI Senators Ronan Mullen and Feargal Quinn are not expected to back Norris.

Of the seven Independent Taoiseach’s nominees, Martin McAleese and Eamonn Coghlan have indicated they will not back anybody while Jillian Van Turnhout will not support Norris.

Some of the remaining four senators, Mary Ann O’Brien, Marie Louise O’Donnell, Fiach Mac Conghail and Katherine Zappone, who supported him in his initial bid, might be persuaded to back him again, but it appears unlikely that he will get the backing of all four.

While some Oireachtas members could be persuaded over the final week, it seems very unlikely that Norris can get the nine extra signatures which he requires.

Dana faces an even bigger uphill battle.

At this stage, only one Oireachtas member, TD Mattie McGrath, has indicated his willingness to back her and there seems very little likelihood that she can win over the necessary 19 others in time.